Adding interior insulation on a brick veneer house - Concern about inward solar drive caused moisture issues.
I own a 1929 brick veneer home and have been steadily improving the airtightness and insulation levels. The time has come to consider the exterior walls, which are (from inside to outside) plaster over celotex, 2x4 framing (hybrid balloon framing), ship lap sheathing, tar paper, 3/4" air gap, then brick. The house is 2 stories, and has approximately 2' overhangs. The walls currently have about 1" of insulation in the form of some sort of prairie grass encapsulated in kraft paper, which is nailed in place with 1/4 wood strips.
In an ideal world, we'd tear out the exterior walls, insulate full depth with closed cell spray foam, and then re-install drywall, perhaps with a layer of rigid foam under the drywall to reduce thermal bridging and bring the wall thickness up at least to the original thickness so that baseboards and such can be re-fitted.
Should I be concerned about potential wetting of the sheathing and framing? I'm in a mixed/cold climate in south east MN.
Alternately, I'd also consider low expanding injection foam (though I haven't found a contractor I'd trust yet) or blown cellulose installed from the inside.
The alternate approaches have appeal because of the cost savings and because the existing plaster is in great shape.
Posted Tue, 05/20/2014 - 08:36
Other Questions in Energy efficiency and durability
Since drywall has a permeance of 0.02 liter/sec - m at 75 PA is ever possible to have sheathing dry to the interior of the home?